The next time you hear people arguing about nature versus nurture in the area of neuroscience, tell them to cut it out. Nature versus nurture is no longer a meaningful debate, according to Mriganka Sur, wriging in the Dec 12, 2008 edition of Science (available online only to subscribers):
Among developmental neuroscientists the debate between nature and nurture has become outmoded. We now know that there is no such thing as a gene that acts in isolation and that every gene needs an environment — whether the environment is the presence of molecules made by other genes, signals generated internally within the developing nervous system, or electrical activity transduced from the external world. Thus, the discussion within the field has moved from nature versus nurture to the integration of nature and nurture and even beyond, to the nature of nurture — which kinds of environmental influences can affect gene expression at specific time points of development.
Hmm. Not sure exactly what he's saying here. A gene for brown eyes is going to result in brown eyes regardless of the environment. It is not going to express blue eyes or a third big toe. I agree that environment has an impact on development, specifically when talking about behavior, but I also tend to agree with Steven Pinker in his book, The Blank Slate, where nature takes a much larger role in personality.
I highly recommend this book for anyone interested in the Nature vs. Nurture debate.
I haven't read that book, Kevin, but as the adoptive mother of children whose genetic backgrounds I know next to nothing about, I am interested in how nature and nurture interact. I would think the discussion is much less about physical traits than personality traits, yes? And while I agree with the supposition that we come hard-wired with our personality traits in place, the discussion needs to be how best to nurture those personality traits in such a way that children can grow up into the best possible versions of themselves. Much of doing that involves accepting that they are hard-wired to be who they are and observing them closely to find out who that is – then parenting them in such a way that you sort of coach them into self-awareness, self-satisfaction and self-confidence.
My personal basic theory on "bad" parenting is not finding out who your kid really is and loving them for that. Instead, we try to mold them into some version of offspring we think they should be, and in the process, tell them in a million different ways that who they really are is not good enough, unacceptable, weird – whatever. I will look up Steven Pinker . . .
Neuroscientists, Kevin. You can't affect eye color by nurture, but the debate about how it determines behavior has been around for ages. Even before anything was known about genetics, philosophers and scientists (and others prone to speculation from other walks of life) have blamed or credited personality traits, mental or physical abnormalities, and behavior on one or the other. I've always thought that you can be born with some sort of predilection that could either exhibit itself or remain hidden depending on exposure to a trigger.
For example, we all have the potential to develop cancer. Some cancers are more likely to be found in families, some are more likely to be found in people who are exposed to particular environmental factors. However, not all people with a family history will develop the same or any cancer, just as not all who are exposed to a suspected carcinogen will.
Most parents of multiple children, including identical siblings, will be able to tell you how different the children are despite sharing both genetic traits and family environment. While we're not "tabuli rasi" (Oh, to really remember High School Latin. . .) as the ancients supposed, there's no question that the brain is malleable even when it has inherited structures that affect function.
Despite this article, and many prior decades of research discrediting the whole either/or nature of the question, it probably won't be going away any time soon. It's far easier to pick one or the other, for most people.
nature and nurture meet in epigenetics
Vicki is right about epigenetics. I've discussed that topic generally several times, including here. http://dangerousintersection.org/2006/10/29/it%E2…
See also, the danger of "the gene for x" stories. http://dangerousintersection.org/2008/08/11/our-h…